detecting parallel lines in an image using Frequency domain

Question

I have an image with straight lines. I want to check if the lines are parallels using frequency domain. I\'m doing fft on the image and i get the transform image.

Do

Answer 1

If you are interested in determining the periodicity of many equally spaced parallel lines, than it is OK to use FFT. In this case the FFT transformed image should give you a peak for the specific frequency. By thresholding you can also get rid of these lines in the image. However, you wont actually be finding where the lines are in the image.

For finding parallel lines, you can use other techniques such as:

• Hough transform (not specifically for parallel lines)
• Radon transform (see how to use radon transform for detecting lines)